Audi A5 2009 QUATTRO Tsfi 2.0 - Car shaking due to excess air build up B218700 & P227900 codes

[Tyx98]

Hi, I’m having a few issues with my Audi A5.

Firstly, anytime I start the car on a cold engine the car shakes for a few minutes 2-3 mins due to excess air build up. This is the error codes I get:

P2187 - lean fuel mixture at an idle in either Bank 1 

P2279 - intake air system leak

I tried using fuel injector cleaners and the engine light still keeps coming back with these two codes. Anytime I reset the codes and start the engine the engine excessively shakes for around 3 minutes until I rev the air out. 

I think that the P2279 code is due to some air leak and I am planning to run a smoke test through the engine to detect the leak, if no leak founds I saw somewhere that I should replace the sensor. 

I’ve also saw a video replacing the PCV valve diaphragm could fix the issue. My valve seems fine however I read somewhere that they may look ok but still be at fault. Therefore, I have ordered one and waiting for delivery (see attached photo).

Apart from these two codes popping up and the engine light going off as well as the shakes when starting a cold engine the car runs perfect. 

Anyone had any similar issues or know what the problem could be here?

Edited December 20, 2022 by Tyx98

[Steve Q]

Sounds like you're on the right tracks. Please keep us posted on how you get on.